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std::basic_string_view<CharT,Traits>::max_size

constexpr size_type max_size() const noexcept;
(since C++17)

The largest possible number of char-like objects that can be referred to by a basic_string_view.

Parameters

(none).

Return value

Maximum number of characters.

Complexity

Constant.

Example

#include <iostream>
#include <limits>
#include <string_view>
 
int main() {
    std::cout
        << std::numeric_limits<std::int64_t>::max()
        << " <- numeric_limits<int64_t>::max()\n"
        << std::string_view{}.max_size()
        << " <- std::string_view::max_size()\n"
        << std::basic_string_view<char>{}.max_size()
        << " <- std::basic_string_view<char>::max_size()\n"
        << std::basic_string_view<char16_t>{}.max_size()
        << " <- std::basic_string_view<char16_t>::max_size()\n"
        << std::wstring_view{}.max_size()
        << " <- std::wstring_view::max_size()\n"
        << std::basic_string_view<char32_t>{}.max_size()
        << " <- std::basic_string_view<char32_t>::max_size()\n"
        ;
}

Possible output:

9223372036854775807 <- numeric_limits<int64_t>::max()
4611686018427387899 <- std::string_view::max_size()
4611686018427387899 <- std::basic_string_view<char>::max_size()
2305843009213693949 <- std::basic_string_view<char16_t>::max_size()
1152921504606846974 <- std::wstring_view::max_size()
1152921504606846974 <- std::basic_string_view<char32_t>::max_size()

See also

(C++17)
returns the number of characters
(public member function)
(C++17)
checks whether the view is empty
(public member function)
returns the maximum number of characters
(public member function of std::basic_string<CharT,Traits,Allocator>)

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